1. Field of the Invention
The invention relates to coaxial cable connectors and, more particularly, to a tool for stripping a coaxial cable and for crimp attachment of the stripped coaxial cable to a coaxial cable connector.
2. Prior Art
In recent years, coaxial cables have been required to pass a wider spectrum of signals associated with communication systems such as, for example, Cable TV (CATV), Satellite TV, and off-air programming. Historically, these communication systems have been installed by professional installers who are well-trained and experienced people. Such professional installers employ specialized tools and standardized methods of cable connector installation to: (a) insure proper system performance; and (b) comply with new FCC RF-leakage requirements. Proper attachment of coaxial cable connectors to coaxial cables is required in order to accomplish both goals.
CATV system providers are required to bring their signal conducting cables only to the home entry point; thereby allowing the homeowner to select an independent contractor to wire the interior of his/her house. Alternatively, current regulations enable the homeowner to install the inside cable and connect the last distribution leg to the cable system himself/herself. In the case of satellite signals, the homeowner can install a downlink, or even an uplink, employing his/her choice of cable, cable connectors, preparation tools and methods. In the case of cable TV installations, the homeowner is responsible for preventing RF leakage and can have his/her CATV service terminated if the home installation causes RF signal leakage.
Inexpensive prior art cable stripping tools are available for the non-professional installer. Such tools employ a single blade or a knife blade to cut the insulating jacket, conductive braid, and dielectric material comprising the coaxial cable. The lack of cutting guides and controlled cutting pressure in such devices may result in the installer cutting through the braid, rendering use of the high-shielding braid xe2x80x9cfoldbackxe2x80x9d method for preparing the cable end for attachment to a connector impossible.
Present coaxial connectors that are intended for the do-it-yourself home installation market usually provide a cable connector attachment means consisting of a separate compression crimp ring, usually about xe2x85x9 to xc2xc inch in length, which is slipped over the cable-cable connector assembly and xe2x80x9ccrimpedxe2x80x9d (inelastically deformed inwardly) to effect attachment. The tool used for crimping is usually a pliers or an economy crimp tool with a circular hole in the crimping die. Upon crimping, the xc2xc inch ring is pinched radially inwardly, forming an assembly wherein there is a relatively low retaining force between the prepared end of the cable and the terminal cable connector. The compressed (crimped) ring compresses the cable and the connector together at only 2 points underlying the portions of the compression ring that have been bent almost 90 degrees. Without sufficient holding force, connectors may partially pull off, causing RF leakage.
Prior art economical coaxial cable connector crimping tools lack a crimp die that can crimp a compression ring having a xc2xd inch or greater length and/or lack the means for applying the force required in order to compress the xc2xd inch ring to a hex form. Moreover, the Society of Cable Engineers has established standards for CATV and satellite TV connectors of 40 pounds holding force. Due to the large number of different coaxial cables used with connectors, consistent compliance with this standard is not possible without a longer crimp ring, such as a xc2xd inch crimp ring, and a hexagonal crimp. In addition, the performance standards for simple interior home TV extensions have increased dramatically. There remains a current need for a low cost coaxial cable stripping tool, in combination with a fastening (crimping) tool that may be used by an unskilled person for the leakproof installation of coaxial cable in the home.
Present coaxial cable connection standards require the coaxial cable connector to include an integral crimp or compression ring that is at least xc2xd inch in length in order to provide the minimal level of holding force (40 pounds) and shielding necessary to prevent RF egress from occurring. Such a construction also provides a larger area for application of the force that holds the coaxial cable in attached relationship with the connector. The currently preferred crimp design is one of compressing the original round crimp ring into a hex form. This provides less stress on each of 6 points that have been bent.
Prior art hex pinch crimp tools, both amateur and professional, rely upon the leverage achieved by the length of a pliers type handle to compress the crimp ring. This tool, for handles of reasonable length, still requires great strength to in order to crimp a ring. The present invention creates the required hex compression force using a screw type mechanism. The benefit gained by ease of installation due to increased leverage more than offsets the slightly longer installation time required to affect the hex crimp.
It is a first object of the invention to provide an inexpensive coaxial cable installation tool having means for stripping the end of a coaxial cable in preparation for attachment of the cable to a coaxial cable connector and further includes cable attachment means operable for crimping the stripped end of the cable to the cable connector.
It is a further object of the invention to provide a tool for stripping the end of a coaxial cable in accordance with the above objective wherein the means for stripping comprises a dual blade cutter that has preset blade separation, fixed cutting depths, and preset spring pressure to insure a complete cut.
It is still a further object of the invention to provide an inexpensive coaxial cable installation tool meeting the above objectives wherein the cable attachment means is operable for hexagonally crimping a circular crimping ring on a coaxial cable connector.
It is yet a further object of the invention to provide an inexpensive coaxial cable installation tool meeting the above objectives wherein the cable attachment means is operable for hexagonally crimping a circular crimping ring on a coaxial cable connector that has a crimping ring length of up to one half inch.
The features of the invention believed to be novel are set forth with particularity in the appended claims. However the invention itself, both as to organization and method of operation, together with further objects and advantages thereof may be best be understood by reference to the following description taken in conjunction with the accompanying drawings in which: